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Updated: May 21, 2025
08:29
Analyses of Mitochondrial Calcium Influx in Isolated Mitochondria and Cultured Cells
Published on: April 27, 2018
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TMBIM-2 orchestrates systemic mitochondrial stress response via facilitating Ca2+ oscillations
Jiasheng Li1,2, Jimeng Cui1,2, Xinyu Li1,2
1State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China.
The Journal of Cell Biology
|March 18, 2025
Summary
Mitochondrial stress in neurons triggers calcium signals that activate a protective response. This pathway, mediated by TMBIM-2, improves learning and extends lifespan in aging worms.
Area of Science:
- Neuroscience
- Cellular Biology
- Aging Research
Background:
- Neuronal mitochondrial function is vital for organismal health and inter-tissue communication.
- The molecular mechanisms linking chronic mitochondrial stress in neurons to aging and metabolism are not fully understood.
Purpose of the Study:
- To identify key mediators of the neuronal mitochondrial unfolded protein response (UPRmt).
- To elucidate the role of neuronal mitochondrial stress in regulating calcium signaling, neurotransmission, and aging.
Main Methods:
- Utilized Caenorhabditis elegans as a model organism.
- Investigated the function of the transmembrane protein XBX-6/TMBIM-2 in neuronal UPRmt.
- Analyzed calcium (Ca2+) oscillations, serotonin release, and learning behavior.
Main Results:
- Identified XBX-6/TMBIM-2 as a crucial mediator of neuronal-to-intestinal UPRmt.
- Demonstrated that neuronal mitochondrial stress induces TMBIM-2-dependent Ca2+ oscillations via MCA-3.
- Showed that persistent synaptic Ca2+ oscillations facilitate serotonin release and UPRmt activation.
- Found that TMBIM-2 levels decrease with age, and its overexpression improves aversive learning and extends lifespan.
Conclusions:
- Chronic neuronal mitochondrial stress is integrated into neurotransmission via TMBIM-2-dependent calcium signaling.
- This process drives metabolic adaptation and behavioral modifications that regulate aging.
- TMBIM-2 represents a potential therapeutic target for age-related decline.
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